EP-A-538,977 describes a process for providing a solvent-spun cellulose fibre with a reduced fibrillation tendency, in which process the fibre is treated with a chemical reagent having two to six functional groups reactive with cellulose. It states that the untreated fibre and the treated fibre are preferably of substantially the same colour and that the functional groups reactive with cellulose are those generally used in fibre-reactive dyes for cellulose, for example as described in an article entitled "Dyes, Reactive" in Kirk-Othmer, Encyclopaedia of Chemical Technology, 3rd edition, Volume 8 (1979, Wiley-Interscience) at pages 374-392. Preferred examples of such functional groups are said to be reactive halogen atoms attached to a polyazine ring, for example fluorine, chlorine or bromine atoms attached to a pyridazine, pyrimidine or sym-triazine ring. Other examples of such functional groups are said to include vinyl sulphones and precursors thereof. The great majority of the chemical reagents utilised in the Examples in EP-A-538,977 contain halogen atoms attached to a polyazine ring as the only functional groups reactive with cellulose, but one commercial dyestuff which is used in the Examples contains as the functional groups one chlorine atom and one vinyl sulphone group attached to a triazine ring.
FR-A-2273091 describes a method of manufacturing polynosic viscose rayon fibre with reduced tendency to fibrillation. In that method the fibre is treated in the primary gel state characteristic of polynosic viscose rayon manufacture with a crosslinking agent containing at least two acrylamido groups and an alkaline catalyst. This primary polynosic gel is a highly swollen gel having a water imbibition of 190-200%, which is found only in polynosic viscose rayon that has never been dried. Water imbibition is defined as the weight of water retained per unit weight of bone-dry material. By way of comparison, never-dried conventional viscose rayon fibre is known generally to have a water imbibition in the range 120-150%. Triacryloyl-hexahydro-1,3,5-triazine and N,N'-methylenebisacrylamide are mentioned in FR-A-2273091 as preferred examples of crosslinking agent.